In the Second Treatise on Government and A Letter Concerning Toleration, Locke spells out the hitherto only implied concept of human rights presumed by the concept of natural law. These include the right of property, which is derived from what is removed from the state of nature by the work of man’s body and his hands. To protect this property and to govern other aspects of human relationships and rights, civil society is established. Professor Konvitz explains the interaction of Marxist thought with this labor theory of property. He also mentions the other inalienable rights that Locke identifies as life, property, religion, and the right to raise and educate a family.